Re: BUG #18541: Reattaching a partition referenced by a foreign key fails with an error

Alvaro Herrera <alvherre@alvh.no-ip.org>

From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Tender Wang <tndrwang@gmail.com>
Cc: exclusion@gmail.com, pgsql-bugs@lists.postgresql.org
Date: 2024-08-07T18:44:55Z
Lists: pgsql-bugs
On 2024-Jul-15, Tender Wang wrote:

> PG Bug reporting form <noreply@postgresql.org> 于2024年7月15日周一 21:02写道:
> 
> > The following script:
> > CREATE TABLE t1 (a int, PRIMARY KEY (a));
> > CREATE TABLE t (a int, PRIMARY KEY (a), FOREIGN KEY (a) REFERENCES t1)
> > PARTITION BY LIST (a);
> > ALTER TABLE t ATTACH PARTITION t1 FOR VALUES IN (1);
> > ALTER TABLE t DETACH PARTITION t1;
> > ALTER TABLE t ATTACH PARTITION t1 FOR VALUES IN (1);
> >
> > ends up with the error complaining about check triggers:
> > ERROR:  XX000: could not find ON INSERT check triggers of foreign key
> > constraint 16400
> > LOCATION:  GetForeignKeyCheckTriggers, tablecmds.c:11260

> I saw the same error in [1]. I guess it is same issue.
> I send a patch in [1], but it may need a more work.

I think this schema is nuts.  Do you have a practical use for something
like this?

I am tempted to fix this by dictating that you can't join a table as a
partition if the partitioned table contains an FK that references that
table.

FWIW the patch I have fixes all the other reported problems with FKs and
partitioned tables, but not this one.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/



Commits

  1. Restructure foreign key handling code for ATTACH/DETACH

  2. Refuse ATTACH of a table referenced by a foreign key